Font size different in preview then compose/read window


I have em Client 7.0 and Windows 10 home.

When looking at an email in the preview pane, the font size is nice and big (as specified.)  However, if I double click to open up an email into its own window, the font size used to display the message is much smaller.  Can I fix this to that it is the same sized used in the preview pane?

Also, the font size used when creating a message (specified at 16 point) looks more like it is 10 point.  Again, the compose window is a separate window.

So when em Client opens up a separate window, it seems to use a different font size than what is specified in the settings.  How do I control the font size used in the separate window?

Thanks for the help,